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The Active Jet in NGC 4258 and Its Associated Shocks
Pérez-Fournon, I.; Wilson, A. S.; Nagar, N. +6 more
We present images and spectra of the active jet and anomalous arms on subparsec through kiloparsec scales in the LINER/Seyfert galaxy NGC 4258 (M106). New VLBA and multiconfiguration VLA images show that, on 0.3-300 pc scales, the jet in projection aligns with (1) the spin axis of the underlying accretion disk and (2) two radio hot spots 24" S (84…
The Evolution of Early-Type Galaxies in Distant Clusters. I. Surface Photometry and Structural Parameters for 53 Galaxies in the z=0.33 Cluster CL 1358+62
van Dokkum, Pieter G.; Franx, Marijn; Kelson, Daniel D. +1 more
Using wide-field, two-color Hubble Space Telescope (HST) imaging of the cluster Cl 1358+62 (z=0.33), we derive structural parameters for a large, magnitude-limited sample of cluster members. These structural parameters are combined with accurate velocity dispersions in another paper to investigate the fundamental plane in the cluster. We fit integ…
The Starfish Twins: Two Young Planetary Nebulae with Extreme Multipolar Morphology
Sahai, Raghvendra
We present Hα images of two objects, He 2-47 and M1-37, obtained during a Hubble Space Telescope imaging survey of young planetary nebulae (PNs) selected on the basis of their low-excitation characteristics. The two objects show a highly aspherical morphology, characterized by multiple lobes distributed around the central star. Such a morphology h…
Chandra X-Ray Observatory Arcsecond Imaging of the Young, Oxygen-rich Supernova Remnant 1E 0102.2-7219
Smith, Randall K.; Plucinsky, Paul P.; Gaetz, T. J. +4 more
We present observations of the young, oxygen-rich supernova remnant 1E 0102.2-7219 taken by the Chandra X-Ray Observatory during its orbital activation and checkout phase. The boundary of the blast-wave shock is clearly seen for the first time, allowing the diameter of the remnant and the mean blast-wave velocity to be determined accurately. The p…
Jet-induced Star Formation in Centaurus A
Calzetti, Daniela; Ballester, Gilda E.; Grillmair, Carl +20 more
The inner part of the northeast middle radio lobe of the radio galaxy Centaurus A is the site of complex interactions. This area contains a large H I cloud as well as filaments of ionized gas and associated blue knots, several of which exist along the northeastern edge of the radio-emitting zones. We observed the filaments and blue knots with the …
Infrared Space Observatory Spectroscopy of Extreme Carbon Stars
Volk, Kevin; Kwok, Sun; Xiong, Guan-Zhu
We present Infrared Space Observatory (ISO) SWS01 (2-43 µm) and LWS01 (43-195 µm) observations of five highly evolved carbon stars with extremely thick circumstellar envelopes. The unidentified 30 µm emission feature is detected in the SWS01 spectra of all five sources. This feature seems to be resolved into two subfeatures at 25…
Ultracompact X-Ray Binaries in Globular Clusters: Variability of the Optical Counterpart of X1832-330 in NGC 6652
Anderson, Scott F.; Margon, Bruce; Deutsch, Eric W.
Evidence is emerging that the luminous X-ray sources in the cores of globular clusters may often consist of, or perhaps even as a class be dominated by, ultracompact (P<~1 hr) binary stars. To the two such systems already known, in NGC 6624 and NGC 6712, we now add evidence for two more. We detect large-amplitude variability in the candidate op…
Near-Infrared Imaging Polarimetry of the GG Tauri Circumbinary Ring
Duchêne, Gaspard; Gledhill, Tim; Ménard, François +1 more
We present 1 µm Hubble Space Telescope/near-infrared camera and multiobject spectrometer resolved imaging polarimetry of the GG Tau circumbinary ring. We find that the ring displays east-west asymmetries in surface brightness as well as several pronounced irregularities but is smoother than suggested by ground-based adaptive optics observati…
The Resolved Narrow-Line Region in NGC 4151
Gull, T. R.; Kraemer, S. B.; Crenshaw, D. M. +6 more
We present slitless spectra of the narrow-line region (NLR) in NGC 4151 from the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope and investigate the kinematics and physical conditions of the emission-line clouds in this region. Using medium resolution (~0.5 Å) slitless spectra at two roll angles and narrow-band undisperse…
Hubble Space Telescope Space Telescope Imaging Spectrograph Imaging of the Host Galaxy of GRB 980425/SN 1998BW
Tanvir, N.; Hjorth, J.; Björnsson, G. +6 more
We present Hubble Space Telescope Space Telescope Imaging Spectrograph observations of ESO 184-G82, the host galaxy of the gamma-ray burst GRB 980425 associated with the peculiar Type Ic supernova SN 1998bw. ESO 184-G82 is found to be an actively star-forming SBc subluminous galaxy. We detect an object consistent with being a point source within t…